639337056 has 48 divisors (see below), whose sum is σ = 1732405248. Its totient is φ = 206236800.

The previous prime is 639337031. The next prime is 639337063. The reversal of 639337056 is 650733936.

It is a tau number, because it is divible by the number of its divisors (48).

It is a junction number, because it is equal to n+sod(n) for n = 639336999 and 639337017.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 104440 + ... + 110391.

It is an arithmetic number, because the mean of its divisors is an integer number (36091776).

Almost surely, 2^639337056 is an apocalyptic number.

It is an amenable number.

639337056 is an abundant number, since it is smaller than the sum of its proper divisors (1093068192).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

639337056 is a wasteful number, since it uses less digits than its factorization.

639337056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214875 (or 214867 counting only the distinct ones).

The product of its (nonzero) digits is 306180, while the sum is 42.

The square root of 639337056 is about 25285.1153052542. The cubic root of 639337056 is about 861.4762170559.

The spelling of 639337056 in words is "six hundred thirty-nine million, three hundred thirty-seven thousand, fifty-six".